The present invention, in some embodiments thereof, relates to a robotic platform and, more particularly, but not exclusively, to a robotic platform having one or more obstacle climbing flipper moving mechanism.
Flippers are used in robotic platforms for climbing obstacles such as stairs, rocks and slopes. Couture et al. (U.S. Patent Publication No. 2009/0314554) describe a mobile robot with two sets of left and right driving flipper associated with a chassis. In some implementations, each flipper is independently rotatable about a pivot axis with respect to the chassis allowing the chassis to tilt about the pivot axis with respect to the first and second sets of flippers.
Robotic arms are mounted on robotic platforms in a few typical configurations. Jacobsen (U.S. Patent Publication No. 2008/0167752) discloses a tracked robotic crawler with at least one articulated arm which moves relative to the frame unit in at least one dimension. Carr et al. (U.S. Pat. No. 4,621,562) discloses an unmanned remote control robot vehicle comprising a first arm having first and second ends, wherein said first end of said arm is pivotally connected to torrent assembly. The torrent assembly is rotatably connected to a chassis.
Robotic arms typically comprise a plurality of articulated links. Hinge joints can be used at alternating angles (eg perpendicular to each other) to improve flexibility of shape. In robotic arms the last element in the system, i.e. the wrist, generally has a moveable end effector to which is attached a gripper or some other tool. Several strategies are known in the art to replace end effectors. Hennekes et al. (U.S. Pat. No. 4,996,753) describe a robot end effector exchange system which permits use of a plurality of different end effectors. Dunning et al. (U.S. Pat. No. 5,860,900) describe an end effector storage station which stores end effectors in a horizontal and cantilevered position. The robot end effector exchange system also permits attachment and detachment of the end effector as a result of simple linear motion of the robot arm. Hennekes et al. (U.S. Pat. No. 4,512,709) describes a machine mechanism which utilizes an interchangeable plurality of tools.
Many robotic platforms use mechanisms for to eliminate reaction forces generated by robot manipulation, for example counterweights. Another mechanism is taught in Brow and Mass (U.S. Pat. No. 5,214,749) which discloses a robotic platform with a dynamically controlled center of mass having a dynamic controller for moving the robot arms so that for each dimension of movement of the end effector there are two degrees of freedom of the robot arm to decouple the center of mass from the end effector. Lindholm et al. (U.S. Pat. No. 4,695,027) disclose how to arrange a second robotic arm and a counterweight to be displaceable on the primary arm the center of gravity of the arm system is situated in immediate proximity to the pivotal axis of the primary arm on the stand, whereby the secondary arm and the counterbalance are at the same time linearly displaceable towards and away from each other, respectively, on respective sides of the pivot axis by means of a movement-transmitting mechanism.